The present invention relates to an imaging device, a method of controlling an imaging device, and the like.
An imaging device (camera) may be provided with a blur correction function (image stabilization function) in order to prevent a deterioration in captured image due to shake (motion) of the imaging device (camera) during the imaging (capture) operation. The blur correction technique may be roughly classified into the following three techniques.
The first technique is an optical blur correction technique that detects the motion (vibrations) of the imaging device using a motion sensor (e.g., angular velocity sensor or acceleration sensor), and corrects blurring by driving an optical system (e.g., lens or variable apex angle prism) corresponding to the detected motion amount (see JP-A-61-240780 and JP-A-61-223819, for example).
The second technique provides only a shake detection motion sensor in the imaging device to record shake information, and corrects blurring by performing a blur correction process during viewing using the shake information (see JP-A-6-276512, JP-A-6-343159, and JP-A-7-226905, for example).
The third technique acquires (calculates) blur information from the captured image, and performs a blur correction process using the blur information when reading the image. For example, the non-blurred image is restored from the deteriorated image by digital processing (e.g., inverse filter, Wiener filter, or Richardson-Lucy method).
A technique that improves the frequency characteristics of the point spread function during the imaging operation, and then performs a blur correction process has also been known. For example, JP-T-2009-532928 and JP-T-2009-522825 improve the frequency characteristics of the point spread function during the imaging operation by quickly and repetitively opening and closing (hereinafter referred to as “fluttering”) the shutter at a given timing to implement a more accurate blur correction process. JP-A-61-240780 improves the frequency characteristics of the point spread function during the imaging operation by utilizing a coded aperture as the aperture of the imaging device to implement a more accurate blur correction process.